Mix sour cream and 1/2 ts. Dill weed; cover and refrigerate.

Heat oven to 400 F. Grease pie plante 9x1 1/4" or 10x1 1/2". Sprinkle tuna and 1/2 ts. Dill weed in plate. Beat remaining ingredients until smooth, 15 seconds in blender on high or 1 minute with hand beater. Pour into plate. Bke until knife inserted in center comes out clean, about 35 minutes. Cool 5 minutes. Serve with sour cream mixture.